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CME / EMP

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Nov 25th 2012, 20:54
K7RAH Joined: Apr 4th 1998, 00:00 Total Topics: 0 Total Posts: 0	NASA has predicted the possability of some major solar storms this year through 2013, with the activity peaking in 2013. Recent massive coronal ejections (CME'S) have been recorded as recent as November, 16, 2012, when A giant solar prominence erupted from the sun. Luckily the eruption was not directed toward the earth. The worse recorded solar storm occurred back in September of 1859. I have heard very little about what might be considered in order to protect sensitive radio and electronic equipment in the event of such a solar event. All I can think of is a well sheilded metal enclosure, like a box that is grounded. This would provide a Faraday shielded protection. Any comment or suggestions?
Nov 26th 2012, 11:56
W1VT Super Moderator Joined: Apr 4th 1998, 00:00 Total Topics: 0 Total Posts: 0	You can go to our lightning protection page to find a comprehensive 4 part series on protecting your gear. http://www.arrl.org/lightning-protection Zack Lau W1VT ARRL Senior Lab Engineer
Nov 26th 2012, 15:26
aa6e Joined: Apr 4th 1998, 00:00 Total Topics: 0 Total Posts: 0	I'm not aware of any danger to ham equipment from solar flares or CMEs. They do have major impact on propagation conditions, but that won't harm your equipment. The big worry from a major solar event (and subsequent geomagnetic storm) is that it may cause serious damage to the power grid. The changes in magnetic field induce large low-frequency ("DC") currents in transmission lines that can burn out big transformers. The only thing a ham can do is to maintain a good emergency power source. Your posting title mentions "EMP". The term Electromagnetic Pulse (EMP) usually refers to the serious electrical effects of high-altitude nuclear explosions. A very bad thing, but not related to the sun. EMP, if it happens, is even worse than lightning. The pulse is extremely sharp (5 nsec) and powerful (up to possibly 6 megawatts per square meter!) It can spread over hundreds or thousands of miles, wiping out most modern electronics gear. Keep vacuum tube radios handy, and keep them disconnected from power and antenna wires! (Ref: Wikipedia EMP article.) Protection from EMP is similar to lightning protection. Careful attention to shielding and grounding, along with surge protection on all incoming wiring. However, EMP-designed suppression devices are relatively rare and expensive. Ordinary lightning protection used by hams probably won't do the job, because of the very fast rise-time of EMP. 73 Martin AA6E ARRL Technical Advisor
Nov 27th 2012, 00:24
K7RAH Joined: Apr 4th 1998, 00:00 Total Topics: 0 Total Posts: 0	Quote by W1VT You can go to our lightning protection page to find a comprehensive 4 part series on protecting your gear. http://www.arrl.org/lightning-protection Zack Lau W1VT ARRL Senior Lab Engineer =============================== Thank you for your information, I will review the infomation from the link provideid. Richard /K7RAH
Nov 27th 2012, 04:02
K7RAH Joined: Apr 4th 1998, 00:00 Total Topics: 0 Total Posts: 0	Quote by AA6E I'm not aware of any danger to ham equipment from solar flares or CMEs. They do have major impact on propagation conditions, but that won't harm your equipment. The big worry from a major solar event (and subsequent geomagnetic storm) is that it may cause serious damage to the power grid. The changes in magnetic field induce large low-frequency ("DC") currents in transmission lines that can burn out big transformers. The only thing a ham can do is to maintain a good emergency power source. Your posting title mentions "EMP". The term Electromagnetic Pulse (EMP) usually refers to the serious electrical effects of high-altitude nuclear explosions. A very bad thing, but not related to the sun. EMP, if it happens, is even worse than lightning. The pulse is extremely sharp (5 nsec) and powerful (up to possibly 6 megawatts per square meter!) It can spread over hundreds or thousands of miles, wiping out most modern electronics gear. Keep vacuum tube radios handy, and keep them disconnected from power and antenna wires! (Ref: Wikipedia EMP article.) Protection from EMP is similar to lightning protection. Careful attention to shielding and grounding, along with surge protection on all incoming wiring. However, EMP-designed suppression devices are relatively rare and expensive. Ordinary lightning protection used by hams probably won't do the job, because of the very fast rise-time of EMP. 73 Martin AA6E ARRL Technical Advisor ========================== Thank you for the clarifications. I had believed radios would be at risk. Richard / K7RAH